04-23-2018, 09:40 AM
Sorry, that was not enough explanation. I'm so used to sharpening on Kallys that that's just where my mind goes. IMHO, 1700 SFPM is simply too fast for well controlled metal removal. I'm not dismissing belt machines for sharpening all knives. Especially if you can turn the speed down. That is by far the biggest thing.
The reason I put Mr. Grepper into a different class is because he constantly speaks of a different level of pressure than anything I've ever seen, and no one else spends nearly as much time on a belt. I know he can achieve that with a blade rest, and I'm not sure there is another way. The consistency of his BESS scores is absolutely remarkable, which I think is very significant.
Cutting belt speed by 2/3 on his Viel gives Mr. Ken very much more control. That's huge, and Mr. Ken can take it a step farther with a very low speed Tormek, and benefits from the precision of a clamped jig system. Mr. KG takes the same platform, combined with dynamic software steroids and kicks every knife out at an astounding level of precision.
I'm not even slightly concerned about anyone building heat, even with normal pressure on a Kally. By the time you're proficient on a Kally, you know how quickly worn belts build heat. It's pretty obvious when a belt has given up a sharp scratch pattern, which is before it really builds heat. No worries.
On a Kally, rate of metal removal can be devastating. You will have "oh s#$t!" moments, where a blade simply vaporizes right before your wondering eyes. With fresh, aggressive belts, it only takes a heartbeat to significantly shorten a small blade, or a soft stainless folder in particular.
"Oversharpening" is real, and far more common than not. Whenever you hear of someone dealing with a large burr, about 95% of the time it's on a belt, and totally unnecessary IMHO. It's pretty uncommon to generate a large burr on stones. Not impossible, especially on very coarse diamond stones, but it doesn't happen in two seconds like it does on a belt. Sometimes guys will think that totally removing all traces of a chip is necessary. It's not. It's Way better to remove it in due course. Just because you can take that much steel off in a few seconds on a belt doesn't mean it's best. Inexpensive knives suffer far less though.
The most insidious outcome of sharpening on a 1700 SFPM belt is the "cumulative affect" of metal removal, which is much sneakier. It involves expensive EDC knives, and it's a heart breaker. With a coarse belt, this is simply guaranteed to disappoint. I don't even think a light touch and knife rest can help.
I have a couple significant knives that were victims of the cumulative affect of high belt speed. Even with fine belts, frequent sharpening will remove a lot of blade steel over time. S30VN was kind of an unknown quantity at that time. It won't stay sharp like I prefer. In less than a couple years I suddenly realized that I'd ground away 1/3 of the blades. Using up a couple $400 blades that quickly really freaked me out.
When I'm event sharpening, I see a preponderance of inexpensive knives that probably haven't ever been sharpened, so that makes all the difference in the world.
When I set the bevels on new blades, I use a belt, but it's 2" wide and absolutely creeeeeeping. A TW90 (and Kevin's Viel, I bet) can run just fine at about 75 SFPM. That's 12X slower than a Veil, and 23X slower than a Kally, but it still only takes one minute to achieve an edge. If you spend two minutes at 75 SFPM you just wasted a bunch of steel. When you live with this on a daily basis, it's infinitely poignant.
I've approximated hand sharpening to be less than 10 SFPM. That's simply a different world for control ability. Additionally, you have a nice big patch of dead flat stone, which is not comparable to the 1" width of a belt. You really can't wobble on a stone, but it's easy to wobble on 1" of contact surface. For precision sharpening there just is no comparison.
The other things in need of consideration are the price and size of the blades. Pocket knives and neck knives have small blades. My pocket knives run from $250-$1000. Forged neck knives are $500-$1500. There simply isn't any room for error in any way.
With larger kitchen knives, it's all about precision, and the large contact area vs the small one is paramount. IMHO, you probably won't see many people sharpening Japanese kitchen knives on anything except stones. If they can't freehand, they either use guided equipment or send out for sharpening.
Many knifemakers sharpen their knives for little to nothing. I'm happy to sharpen the knives I make for free. I want them to look and perform their best. Hardly anyone can do that for themselves.
As I said, I've been sharpening on stones for several decades, and it's easy for me. Murray Carter sharpens every knife he sells by hand. So does Ed Fowler. So do most people who make or use high end knives, and anyone who uses razors, so I don't think I'm out of line in any way. Actually completely normal IMHO.
The reason I put Mr. Grepper into a different class is because he constantly speaks of a different level of pressure than anything I've ever seen, and no one else spends nearly as much time on a belt. I know he can achieve that with a blade rest, and I'm not sure there is another way. The consistency of his BESS scores is absolutely remarkable, which I think is very significant.
Cutting belt speed by 2/3 on his Viel gives Mr. Ken very much more control. That's huge, and Mr. Ken can take it a step farther with a very low speed Tormek, and benefits from the precision of a clamped jig system. Mr. KG takes the same platform, combined with dynamic software steroids and kicks every knife out at an astounding level of precision.
I'm not even slightly concerned about anyone building heat, even with normal pressure on a Kally. By the time you're proficient on a Kally, you know how quickly worn belts build heat. It's pretty obvious when a belt has given up a sharp scratch pattern, which is before it really builds heat. No worries.
On a Kally, rate of metal removal can be devastating. You will have "oh s#$t!" moments, where a blade simply vaporizes right before your wondering eyes. With fresh, aggressive belts, it only takes a heartbeat to significantly shorten a small blade, or a soft stainless folder in particular.
"Oversharpening" is real, and far more common than not. Whenever you hear of someone dealing with a large burr, about 95% of the time it's on a belt, and totally unnecessary IMHO. It's pretty uncommon to generate a large burr on stones. Not impossible, especially on very coarse diamond stones, but it doesn't happen in two seconds like it does on a belt. Sometimes guys will think that totally removing all traces of a chip is necessary. It's not. It's Way better to remove it in due course. Just because you can take that much steel off in a few seconds on a belt doesn't mean it's best. Inexpensive knives suffer far less though.
The most insidious outcome of sharpening on a 1700 SFPM belt is the "cumulative affect" of metal removal, which is much sneakier. It involves expensive EDC knives, and it's a heart breaker. With a coarse belt, this is simply guaranteed to disappoint. I don't even think a light touch and knife rest can help.
I have a couple significant knives that were victims of the cumulative affect of high belt speed. Even with fine belts, frequent sharpening will remove a lot of blade steel over time. S30VN was kind of an unknown quantity at that time. It won't stay sharp like I prefer. In less than a couple years I suddenly realized that I'd ground away 1/3 of the blades. Using up a couple $400 blades that quickly really freaked me out.
When I'm event sharpening, I see a preponderance of inexpensive knives that probably haven't ever been sharpened, so that makes all the difference in the world.
When I set the bevels on new blades, I use a belt, but it's 2" wide and absolutely creeeeeeping. A TW90 (and Kevin's Viel, I bet) can run just fine at about 75 SFPM. That's 12X slower than a Veil, and 23X slower than a Kally, but it still only takes one minute to achieve an edge. If you spend two minutes at 75 SFPM you just wasted a bunch of steel. When you live with this on a daily basis, it's infinitely poignant.
I've approximated hand sharpening to be less than 10 SFPM. That's simply a different world for control ability. Additionally, you have a nice big patch of dead flat stone, which is not comparable to the 1" width of a belt. You really can't wobble on a stone, but it's easy to wobble on 1" of contact surface. For precision sharpening there just is no comparison.
The other things in need of consideration are the price and size of the blades. Pocket knives and neck knives have small blades. My pocket knives run from $250-$1000. Forged neck knives are $500-$1500. There simply isn't any room for error in any way.
With larger kitchen knives, it's all about precision, and the large contact area vs the small one is paramount. IMHO, you probably won't see many people sharpening Japanese kitchen knives on anything except stones. If they can't freehand, they either use guided equipment or send out for sharpening.
Many knifemakers sharpen their knives for little to nothing. I'm happy to sharpen the knives I make for free. I want them to look and perform their best. Hardly anyone can do that for themselves.
As I said, I've been sharpening on stones for several decades, and it's easy for me. Murray Carter sharpens every knife he sells by hand. So does Ed Fowler. So do most people who make or use high end knives, and anyone who uses razors, so I don't think I'm out of line in any way. Actually completely normal IMHO.